Electric load centers are employed to divide incoming electric power from a utility power line into a plurality of circuits, each circuit being controlled by a current monitoring circuit breaker. The electric load center generally consists of an insulated basepan on which several bus bars, neutral bars, neutral tie bars and other electrical components have been secured. The electrical components and basepan are generally enclosed within a protective enclosure. Representative basepans of the prior art are shown, for example, in U.S. Pat. Nos. 4,118,754; 4,536,823; 4,931,898; 5,450,282; 5,696,664 and 5,786,982.
Bus bars, neutral bars, and neutral tie bars have typically been secured to the basepan by common fastening devices such as screws, bolts, and separate snap-in fasteners which consume time to apply and require an inventory of extra parts to achieve assembly of the bar to the basepan. To eliminate the use of such extra parts, prior art has also employed posts which are integral parts of a plastic basepan which are intended to be plastically deformed by the application of ultrasonic or heat energy to deform the post to secure the bars to the basepan. The plastic deformation, often referred to as "heat staking", eliminates the need for separate fasteners, but requires the use of a significant amount of energy during the assembly process to heat the staking posts to the point of plastic deformation. Additionally, such heat staking requires some time to deliver the heat to the plastic to achieve the desired amount of deformation necessary to secure the bar to the basepan, which limits the speed at which assembly can be achieved.
An object of the present invention is to provide an electric load center basepan to which bus bars, neutral bars, neutral tie bars and similar electrical components can be secured without the use of separate or extra parts. It is also an object of the present invention to provide a basepan to which the various bars can be secured quickly and without the aid of devices consuming significant amounts of energy to make the assembly process quicker and lower cost. It is a further object of the present invention to permit the use of bars of the varying thickness to be secured to a common basepan.